The Earth Science Picture of the Day (EPOD) highlights the diverse processes and phenomena which shape our planet and our lives. EPOD will collect and archive photos, imagery, graphics, and artwork with short explanatory captions and links exemplifying features within the Earth system. The community is invited to contribute digital imagery, short captions and relevant links.

Mud Cracks near Trona, California

Mud cracks are ephemeralsedimentary features found not just in dry lands but also in a variety of locations and climates. The cracks featured above were found in a desert wash near Trona, California. A rare rain event had flooded the area forming pools of sediment-laden water. As the sediment settled, the heavier coarse-grained particles collected on the bottom first, followed by finer and finer grained sediments. The last to accumulate was the finest clay particles. After the pooled water evaporated, the sediments began to dry out. The surface clay contained the most water and shrank the most as it dried, resulting in the upward curl of the mud cracks. Note the coarser, deeper material between the cracks. Photo taken on October 12, 2010.